Balanced invalid wheel chair



June 9,1942. EVEREST HAL 2,285,699

BALANCED INVALID WHEEL CHAIR Fil ed Sept. 11, 1940 Patented June 9, 1942 Herbert'A. Everest: and Harry; O. J ennin'gs; Los- Angeles, Calif.

Application September 11, 1940;.S'erialNo: 356,326.

7 Claims.

Our. invention: relates toawheel chair forfian invalid ore type which may be readily propelled by the invalids-themselves or may be readily pushed by'an attendant. In many of these types or chairs particularly where: the patient :propels the chair by the hand engaging either the rim of the wheel oran auxiliary rim secured to the wheel difiiculty haslb'een experienced in? rolling the chair over slight obstructions'such. as the edges of rugs, carpets, door-sills and other slightly raised' ordepressed portions of a flooras occur in a house. Alsoif the" chairisused on the street or yard it has been found somewhatidifficult to move the chairover slight Lob'structions. This applies whether or no the chair is operated b'y-the-invalid or by an attendant; Furthermore certain of the types of invalid chairs which have for instance large main -supporting wheelsfwith relatively small casters in some. types readily become unbalanced so thatthe: invalid in the chair may tilt either forward or b'ackwardizunlss the chair is always being handledv by. an attendant -or considerable care is exercised byithei user to preventsuch tilting-. A...type of'chair'which so- -readily tilts=or inclines; to upset. is 1 very unzcornfortable particularly for inva'lidsl having no use oi th'eirlower extremities.

An object and feature of our invention: is:.the constructionzof; a wheelchair. ofTtheLtypea having a pair of main: larger. supporting; WhEBISL which may have a lim'ited tilting; movement either; forward'lyiori rearward'ly but sti11.;cannot readily upset with. the invali'dssittingirr themhair; In. .order 1 that the chair. may: be srolled: our invention comprehends using. casters whichzmay belocated both forwardly and: rearwardly of. the .tread line of the m'ainwheelsand thus are broughtinto contactIwithra; smoothlground surface when the ohairrtilts'..

Another object and feature of our construc tion .is.in..providing for. thetilting. so. that the casters. either." at: the front. or anther rear are raised. from thegroundfin: which case tha chair and the weight of the invalig risusupported by the tread of the main pair ef'wheels andzeither the.front;or;the-reamcastefsubut notiboth'casters. Such construction the: ore;in.norma:lrmovement has .eitherithe front. or: the: rear; castersrslightly raised: aboveza floor line:allowing ;ready propul.-. sion of 1 the chair over." small r obstructions-as; for instance;if.'.the.tfront casters .areiin contactiwith the 'floorrand imeetiantobstruction'. the chair. may be 'tiltedbackwardly. torraise: such front i-casters contacting-.the rear: casters 2 with; the fioor;

An additional object I. and'afeature" of: our: inven'e tion .is :oonstructingctheechair to ;.be substantially balanced-2 when. am inva1id1.;is. .sittingqion. the seat.

in an substantially upright position wherebysthe center :of :gravityrisin. line. With-the. vertical. plane through: the; axles; of the main. wheels. This causes'emost .of: the; weight of theinvalid. and i the chair to::be supported; by. the treadlof the main wheelsswithz very. 1ittle..weight1. or pressure on theacasterrwheels. hence-the chairmay: readily be rocked or.- tiltedi byxth'e invalid: leaning. either slightly. forwardly: orirearwardly.

Another; object; and. feature of: our. invention iszm'ountirrg the'lmain .andzthetcaster; wheels on an. ampleiframe'or'frames which may beattached. to; a: conventional :chair and'ethus turnisuch .chair intoar. whee-1i chair; This; construction enables a wheel. chair; to be: made. *quiteinexpensively. and byzusing: a: conventionalctype. of folding .chair with our; frames;attaclied thereto azreadilyicollapsible wheel; chairrmay; be.-constructed1. Considered; in more detail our simple framestcomprise.erbottom banto which; the. casterrwheelsat. one; side. may be: connected; at: the front. and: the: rear and a vertical; post; connected; substantially; at. the". mid position; thev post. and: the bottom: bar having suitable: connections; to: the; sides; of the. chair whether: rigidzor folding-.1 andthemainwheels are mounted-"eon". axles connectedztothe posts. This type: of: frame may be; readily bolted .Lto... a chair.

Qurrinvention: is.illustratediinconnection with thaa'ccompanyingzdrawing; inwhich:

Fig. 1.1- ista. side: elevation. showing: the wheeled frame .attachedzto; the .frame. of a .folding chair.

Fig; 2: is '.an;elevation of: oneof the frames. for thelwheelsslooking. from the. inside, the wheels being removed:

Eig. 3-.is:;a.horizontal. section through thewheel postcon.thezline ile-ifofiFiglv 2 in the: direction of the arrows;..th'e axleibeing omitted.

In our constructi'omand: for the sake of Sim.- pli'city and I to adapt: the construction to chairs which may. be owned by-the invalid or purchased, weemployi arframe designated by the assembly numeral II. This has at bottom. bar. l2? (note particularly Fig.2). In: thiskinstance it is. made ofa tube... A.post l3.cextends..upwardly.fromthe center; of the. bottom bar and. is. illustrated. as secured thereto: byfia. weld. The bottomlbaris provided-with perforations [4 through which bolts may be passed for attaching the chairashereunder detailed The post also has a. perforation l5 atithetop through whichabolt may be fitted for attachment to. the chair; Adjacent eachend ofjtheebottombar there are further. perforations l blb'yrwhichzthe casters may be attachedzusing'a bolt or a screw. An axle housing 20 is built into the post l3 by perforating the post at 20 and 20" and fixing a sleeve 2| therein. Such sleeve is internally threaded as indicated at 22 and has one end 23 projecting beyond the post I3, the sleeve being secured in place by welds, hence the axle is engaged in these threads 22 and secured by a lock nut, the wheel being on the side of the projection 23. As the sleeve 2| is firmly secured in the perforations 20' and 20 of the tubular post l3 by welding, this sleeve forms a rigid support for an axle. The sleeve is threaded at the inner portion internally as at 22, that is, the portion facing towards the center of thechair, therefore the axle 26 of the wheel which is likewise threaded at its inner end is inserted in the sleeve and engaged in the threads 22, the axle being threaded through the sleeve a sufiicient distance so that its inner threaded end. is engaged by a lock nut. By this construction the hub of the wheel may be brought to have a desired working fit against the outer projecting portion 23. of the sleeve 2|.

Referring to the wheel assembly as shown in Fig. 1, the pair of main wheels 25 have axles 26 secured in the sleeve 2| of the posts, these axles being in horizontal alignment. The tread 21 of the wheel is illustrated as contacting a horizontal surface such as a floor. The front caster assembly 30 is secured to one end of the frame. N, there being two of these frames, one for each side and the rear caster assembly 3| is attached to the rear of the frame. By this construction. it is preferable to have a pair of front and a pair of rear casters. It will be noted in the illustration that the tread of. the front casters is shown in contact with the horizontal ground surface and the tread of the rear caster is raised above the ground. There is in effect a tilting motion permitted on alignment with the axles secured to the respective. posts.

Our running gear frame having the wheels is shown attached to a chair indicated by the assembly numeral 35. In this illustration a type of folding chair is used. This has two side frames 36 both similar employing a bottom bar 31, an arm rest 38 at the top, a front leg 39 and a rear leg 40. Bolts 4| attach the bottom bar 3! of the chair to the bottom bar |2 of the frame H, such bolts being passed through the perforations I4. A bolt 42 extends through an intermediate horizontal bar 43 connecting the front and rear legs 39 and 4!]. In this construction therefore the chair is only attached to the frame at the three definite points. This particular chair is shown as having front and rear cross braces 45 and 46 pivoted at the bottom as at 41 to the bottom bars 31 and connected at the top to sliding seat bars 48, these sliding vertically in the upper parts of the legs 39 and 40.. The seat made of flexible material is attached to the seat bars- This is a conventional type. of chair having a flexible back 49. connecting upward extensions of the rear legs 40.

While our invention is described as attached to a folding type of chair, the frames may be secured to rigid types, however when assembled the center of gravity of the chair plus the frame with the person sitting on the seat should pass substantially centrally through the vertical line through the axles and hence through the tread 27 of the large or main wheels. As the frame and hence the chair may be considered as suspended. from the pivots of the main wheel axles, it is manifest that there may be a slight rocking or tilting in a front to rear direction to permit either the front set or the rear set of casters to contact the floor. This type of chair may readily be propelled by the invalid sitting in the chair by grasping the rim of the wheel or by a rim attached to the spokes, however the chair may readily be handled by an attendant.

Presuming that the chair is being moved in a forward direction with the front casters in contact with the floor and the rear caster raised, then should the front caster meet an obstruction such as the edge of a rug, a door sill or the like, the invalid may tilt slightly backwardly to thus unbalance the chair bringing the front casters up and the rear casters down. There will then be sufficient clearance underneath the front casters to pass over most obstructions of the type encountered in using these chairs. Due to the large wheels being of much increased diameter over the casters they readily roll over the obstruction and when the rear casters meet the same obstruction the chair may be tilted upwardly to bring weight on the front set of casters raising the rear seat clear of the obstruction, therefore it will be seen that the chair may readily be used to pass over minor obstructions of the type usually met with by an invalid in progressing around the floor of a home or the like.

It will be noted also that our chair may be considered as. a balanced invalid chair in, that as above mentioned there is a substantial balance while the chair is being used but generally either the front or rear set of casters will contact the floor on the same plan as the tread of the large wheels. However no matter whether the invalid using the chair inclines forwardly or rearwardly, the respective casters will engage the floor and prevent the chair upsetting by rocking in a front to rear direction thus adding materially to the safety in the use of the chair.

When our frame is mounted on a fol-ding chair of the type in which the sides come together when the chair is collapsed, it wil1 be seen that our assembly of the attachable frame transforms a conventional, folding chair of the above noted type to a folding wheel chair having the advantages of carrying in an automobile, on trains or for storage purposes.

In view of the fact that the major portion of the weight of the chair and the person therein is carried by the large wheels, there is very little pressure on either the front or rear casters, whichever contact the floor, and hence little likelihood of these casters catching on an obstruction. It is quite apparent that rigid wheels could be utilized instead of casters, incidentally making for a cheaper construction. Due, to the tilting character of the chair, it canv readily be turned even with rigidly mounted front and rear wheels.

Various changes may be made in the details of the construction without departing from the spirit or scope of the invention as defined by the appended claims.

We claim:

1. A wheel chair having a chair framev with a seat thereon, awheel assembly frame including a bar with means securing said bar one on each side to the chair frame, a post extending upwardly from each bar, means securing each post to the chair frame, a pair of main wheels each having an axle mounted on a post, a caster secured to the forward and rearward portions of each bar, the wheel frame and the chair frame being adapted to pivot relative to the axles of the main wheels to bring the front or the rear casters in contact with the same ground surface engaged by the main wheels.

2. In a chair construction in which a chair has two side frames each with legs, a bottom bar and an intermediate bar, a seat extending between the side frames, the combination of two wheel assembly frames each including a bottom bar and a post connected thereto and extending upwardly, means securing the bottom bar of the Wheel frame to the bottom bar of a chair frame, means securing each post to a horizontal intermediate bar, a pair of main wheels journalled on each post, a caster at the forward and rear end of each horizontal bar of the Wheel frame, the wheel frames being connected to the chair frames to permit tilting relative to the axles of the main wheels to bring either the front or rear casters in contact with the same level ground surface engaged by the main wheels.

3. In a wheel chair, a pair of wheel assembly frames each having a horizontal bar and a vertical post, means to secure such frames to a chair, a main wheel journalled on each post and a caster secured to the bar one adjacent its forward and one adjacent its rear end, the bar and post being adapted to tilt when secured to a chair relative to the axles of the main wheels to contact either the front or the rear casters with the same level ground engaged by the main wheels.

4. A wheel chair comprising a chair frame and a pair of wheel assembly frames, each wheel assembly frame having a bottom horizontal bar and a vertical post extending upwardly from substantially the mid position of the bar, means securing the bottom bar and the vertical post respectively to said chair frame, a main wheel journalled on each post and casters secured to the bar one adjacent its forward end and one adjacent its rear end, the bar and post being adapted to tilt when secured to a chair relative to the axles of the main wheels to contact either the front or the rear casters with the same level ground engaged by the main wheels.

5. In a wheel chair a pair of wheel assembly frames each having a bottom horizontal rigid bar and a vertical post extending upwardly therefrom at substantially the center of each bar, means to secure each frame to a chair with the posts positioned at the sides of the chair, each post having a tubular sleeve transverse to the post,a main wheel having a stub axle secured in each sleeve, a caster secured to the forward and the rearward end portions of each bottom bar, the bar and the posts being adapted to tilt when it is secured to a chair relative to the aXles of the main wheels to contact either the front or the rear casters with the same level ground engaged by the main wheels.

6. In a device as described a frame for a wheel chair including a pair of rigid bottom bars and a tubular post attached to each bar and, extending upwardly from substantially the mid position of each bar, each post having diametrical perforations, the perforations in the two posts being in transverse alignment, a sleeve secured in the perforations of each post, a stub axle mounted in each sleeve and. a wheel on each stub axle and means to secure a chair to both bottom bars and both posts.

7. In a device as described a frame for a wheel chair including a pair of tubular posts, means to attach each post to a chair at one side thereof, each post having diametrical perforations, the perforation in the two posts being in transverse alignment, a sleeve secured in the perforations of each post, a stub axle mounted in each sleeve and a wheel on each stub axle.

HERBERT A. EVEREST. 

